Organometallic compound, organic light-emitting device including organometallic compound, and electronic apparatus including organic light-emitting device

ABSTRACT

An organometallic compound, represented by Formula 1: 
       M 1 (Ln 1 ) n1 (Ln 2 ) n2    Formula 1
         wherein Ln 1  is a ligand represented by Formula 1A, Ln 2  is a ligand represented by Formula 1B, n1 is 1 or 2, and n2 is 1 or 2:       

     
       
         
         
             
             
         
       
         
         
           
             wherein, in Formulae 1, 1A, and 1B, X 1  is C or N, X 2  is C or N, CY 1  and CY 2  are each independently a C 5 -C 30  carbocyclic group or a C 1 -C 30  heterocyclic group, CY 3  is a 6-membered N-containing heterocyclic group, a 6-membered N-containing heterocyclic group condensed with a C 5 -C 30  carbocyclic group, or a 6-membered N-containing heterocyclic group condensed with a C 5 -C 30  carbocyclic group or a C 1 -C 30  heterocyclic group, CY 41  is a 5-membered carbocyclic group or a 5-membered heterocyclic group, * and *′ each represent a bonding site to M 1 , and wherein R 10 , R 20  to R 30 , R 40  to R 42 , and b10 to b40 are as provided herein.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based on and claims priority to Korean PatentApplication No. 10-2021-0127542, filed on Sep. 27, 2021, in the KoreanIntellectual Property Office, and all benefits under 35 U.S.C. § 119,the content of which is incorporated by reference herein in itsentirety.

BACKGROUND 1. Field

The present disclosure relates to an organometallic compound, an organiclight-emitting device including the organometallic compound, and anelectronic apparatus including the organic light-emitting device.

2. Description of the Related Art

Organic light-emitting devices (OLEDs) are self-emissive devices whichproduce full-color images. In addition, OLEDs have wide viewing anglesand exhibit excellent driving voltage and response speedcharacteristics.

OLEDs include an anode, a cathode, and an organic layer located betweenthe anode and the cathode and including an emission layer. A holetransport region may be located between the anode and the emissionlayer, and an electron transport region may be located between theemission layer and the cathode. Holes provided from the anode may movetoward the emission layer through the hole transport region, andelectrons provided from the cathode may move toward the emission layerthrough the electron transport region. The holes and the electronsrecombine in the emission layer to produce excitons. The excitons maytransition from an excited state to a ground state, thus generatinglight.

SUMMARY

Provided are an organometallic compound, an organic light-emittingdevice including the organometallic compound, and an electronicapparatus including the organic light-emitting device.

Additional aspects will be set forth in part in the detailed descriptionwhich follows and, in part, will be apparent from the detaileddescription, or may be learned by practice of the presented exemplaryembodiments of the present disclosure.

According to an aspect, an organometallic compound is represented byFormula 1:

M₁(Ln₁)_(n1)(Ln₂)_(n2)   Formula 1

wherein, in Formula 1,

M₁ is a transition metal,

Ln₁ is a ligand represented by Formula 1A,

Ln₂ is a ligand represented by Formula 1B,

n1 is 1 or 2, and

n2 is 1 or 2:

wherein, in Formulae 1A and 1B,

X₁ is C or N, and X₂ is C or N,

CY₁ and CY₂ are each independently a C₅-C₃₀ carbocyclic group or aC₁-C₃₀ heterocyclic group,

CY₃ is a 6-membered N-containing heterocyclic group, a 6-memberedN-containing heterocyclic group condensed with a C₅-C₃₀ carbocyclicgroup, or a 6-membered N-containing heterocyclic group condensed with aC₁-C₃₀ heterocyclic group,

CY₄₁ is a 5-membered carbocyclic group or a 5-membered heterocyclicgroup,

R₁₀, R₂₀ to R₃₀, and R₄₀ to R₄₂ are each independently hydrogen,deuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₁-C₆₀ alkylthio group, asubstituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted orunsubstituted C₁-C₁₀, heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedC₂-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₇-C₆₀ alkyl aryl group, asubstituted or unsubstituted C₇-C₆₀ aryl alkyl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted C₂-C₆₀ alkyl heteroaryl group, asubstituted or unsubstituted C₂-C₆₀ heteroaryl alkyl group, asubstituted or unsubstituted C₁-C₆₀ heteroaryloxy group, a substitutedor unsubstituted C₁-C₆₀ heteroarylthio group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —Ge(Q₁)(Q₂)(Q₃), —N(Q₄)(Q₅),—B(Q₆)(Q₇), —P(Q₈)(Q₉), or —P(═O)(Q₈)(Q₉),

two or more of a plurality of R₁₀(s) are optionally bonded together toform a substituted or unsubstituted C₅-C₃₀ carbocyclic group or asubstituted or unsubstituted C₁-C₃₀ heterocyclic group,

two or more of a plurality of R₂₀(s) are optionally bonded together toform a substituted or unsubstituted C₅-C₃₀ carbocyclic group or asubstituted or unsubstituted C₁-C₃₀ heterocyclic group,

two or more of a plurality of R₃₀(s) are optionally bonded together toform a substituted or unsubstituted C₅-C₃₀ carbocyclic group or asubstituted or unsubstituted C₁-C₃₀ heterocyclic group,

two or more of a plurality of R₄₀(s) are optionally bonded together toform a substituted or unsubstituted C₅-C₃₀ carbocyclic group or asubstituted or unsubstituted C₁-C₃₀ heterocyclic group,

two or more adjacent groups of R₁₀, R₂₀, R₃₀, and R₄₀ to R₄₂ areoptionally bonded together to form a substituted or unsubstituted C₅-C₃₀carbocyclic group or a substituted or unsubstituted C₁-C₃₀ heterocyclicgroup,

b10, b20, and b30 are each independently 1, 2, 3, 4, 5, 6, 7, 8, 9, or10,

b40 is 1, 2, 3, 4, 5, or 6, and

at least one substituent of the substituted C₅-C₃₀ carbocyclic group,the substituted C₁-C₃₀ heterocyclic group, the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₁-C₆₀ alkylthio group, the substituted C₃-C₁₀ cycloalkyl group, thesubstituted C₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenyl group, thesubstituted C₆-C₆₀ aryl group, the substituted C₇-C₆₀ alkyl aryl group,the substituted C₇-C₆₀ aryl alkyl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted C₂-C₆₀ alkyl heteroaryl group, thesubstituted C₂-C₆₀ heteroaryl alkyl group, the substituted Fheteroaryloxy group, the substituted C₁-C₆₀ heteroarylthio group, thesubstituted monovalent non-aromatic condensed polycyclic group, and thesubstituted monovalent non-aromatic condensed heteropolycyclic group is:

deuterium, —F, —Cl, —Br, —I, —SF₅, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid group or a salt thereof, a sulfonic acid group or a salt thereof, aphosphoric acid group or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, or aC₁-C₆₀ alkylthio group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, or a C₁-C₆₀ alkylthio group, each substituted withat least one of deuterium, —F, —Cl, —Br, —I, —SF₅, —CD₃, —CD₂H, —CDH₂,—CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitro group, anamino group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₇-C₆₀ alkylaryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a C₂-C₆₀ alkyl heteroaryl group, a C₁-C₆₀heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃),—Ge(C)₁₁)(Q₁₂)(Q₁₃), —N(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), —P(Q₁₈)(Q₁₉),—P(═O)(Q₁₈)(Q₁₉), or a combination thereof;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₇-C₆₀ alkyl aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀ heteroaryl group, a C₂-C₆₀ alkyl heteroarylgroup, a C₁-C₆₀ heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, amonovalent non-aromatic condensed polycyclic group, or a monovalentnon-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₇-C₆₀ alkyl aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀ heteroaryl group, a C₂-C₆₀ alkyl heteroarylgroup, a C₁-C₆₀ heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, amonovalent non-aromatic condensed polycyclic group, or a monovalentnon-aromatic condensed heteropolycyclic group, each substituted with atleast one of deuterium, —F, —Cl, —Br, —I, —SF₅, —CD₃, —CD₂H, —CDH₂,—CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitro group, anamino group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, a C₁-C₆₀ alkylthio group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₇-C₆₀ alkyl arylgroup, a C₇-C₆₀ aryl alkyl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀ heteroaryl group, a C₂-C₆₀ alkyl heteroarylgroup, a C₂-C₆₀ heteroaryl alkyl group, a C₁-C₆₀ heteroaryloxy group, aC₁-C₆₀ heteroarylthio group, a monovalent non-aromatic condensedpolycyclic group, a monovalent non-aromatic condensed heteropolycyclicgroup, —Si(Q₂₁)(Q₂₂)(Q₂₃), —Ge(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₄)(Q₂₅),—B(Q₂₆)(Q₂₇), —P(Q₂₈)(Q₂₉), —P(═O)(Q₂₈)(Q₂₉), or a combination thereof;or

—Si(Q₃₁)(Q₃₂)(Q₃₃), —Ge(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₄)(Q₃₅), —B(Q₃₆)(Q₃₇),—P(Q₃₈)(Q₃₉), or —P(═O)(Q₃₈)(Q₃₉),

wherein Q₁ to Q₉, Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁ to Q₃₉ are eachindependently hydrogen, deuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxylgroup, a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, a phosphoric acidgroup or a salt thereof, a substituted or unsubstituted C₁-C₆₀ alkylgroup, a substituted or unsubstituted C₂-C₆₀ alkenyl group, asubstituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₁-C₆₀alkylthio group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group,a substituted or unsubstituted heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedheterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₇-C₆₀ alkyl aryl group, asubstituted or unsubstituted C₇-C₆₀ aryl alkyl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted C₂-C₆₀ alkyl heteroaryl group, asubstituted or unsubstituted C₂-C₆₀ heteroaryl alkyl group, asubstituted or unsubstituted C₁-C₆₀ heteroaryloxy group, a substitutedor unsubstituted C₁-C₆₀ heteroarylthio group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, or asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group.

According to another aspect, an organic light-emitting device includes:a first electrode; a second electrode; and an organic layer locatedbetween the first electrode and the second electrode, wherein theorganic layer includes an emission layer, and wherein the organic layerfurther includes at least one of the organometallic compound.

The organometallic compound may be included in the emission layer of theorganic layer, and the organometallic compound included in the emissionlayer may serve as a dopant.

According to still another aspect, an electronic apparatus includes theorganic light-emitting device.

BRIEF DESCRIPTION OF THE DRAWING

The above and other aspects, features, and advantages of certainexemplary embodiments of the disclosure will be more apparent from thefollowing detailed description taken in conjunction with theaccompanying drawing, in which the FIGURE is a schematic cross-sectionalview of an organic light-emitting device according to one or moreembodiments.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary embodiments, examplesof which are illustrated in the accompanying drawing, wherein likereference numerals refer to like elements throughout. In this regard,the present exemplary embodiment may have different forms and should notbe construed as being limited to the detailed descriptions set forthherein. Accordingly, the exemplary embodiments are merely describedbelow, by referring to the figure, to explain particular aspects.

The terminology used herein is for the purpose of describing one or moreexemplary embodiments only and is not intended to be limiting. As usedherein, the singular forms “a,” “an,” and “the” are intended to includethe plural forms as well, unless the context clearly indicatesotherwise. The term “or” means “and/or.” It will be further understoodthat the terms “comprises” and/or “comprising,” or “includes” and/or“including” when used in this specification, specify the presence ofstated features, regions, integers, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, regions, integers, steps, operations, elements,components, and/or groups thereof. As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items. Expressions such as “at least one of,” when preceding alist of elements, modify the entire list of elements and do not modifythe individual elements of the list.

It will be understood that, although the terms first, second, third etc.may be used herein to describe various elements, components, regions,layers, and/or sections, these elements, components, regions, layers,and/or sections should not be limited by these terms. These terms areonly used to distinguish one element, component, region, layer, orsection from another element, component, region, layer, or section.Thus, a first element, component, region, layer, or section discussedbelow could be termed a second element, component, region, layer, orsection without departing from the teachings of the present embodiments.

Exemplary embodiments are described herein with reference to crosssection illustrations that are schematic illustrations of idealizedembodiments. As such, variations from the shapes of the illustrations asa result, for example, of manufacturing techniques and/or tolerances,are to be expected. Thus, embodiments described herein should not beconstrued as limited to the particular shapes of regions as illustratedherein but are to include deviations in shapes that result, for example,from manufacturing. For example, a region illustrated or described asflat may, typically, have rough and/or nonlinear features. Moreover,sharp angles that are illustrated may be rounded. Thus, the regionsillustrated in the figures are schematic in nature and their shapes arenot intended to illustrate the precise shape of a region and are notintended to limit the scope of the present claims.

It will be understood that when an element is referred to as being “on”another element, it can be directly in contact with the other element orintervening elements may be present therebetween. In contrast, when anelement is referred to as being “directly on” another element, there areno intervening elements present.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this general inventive conceptbelongs. It will be further understood that terms, such as those definedin commonly used dictionaries, should be interpreted as having a meaningthat is consistent with their meaning in the context of the relevant artand the present disclosure, and will not be interpreted in an idealizedor overly formal sense unless expressly so defined herein.

“About” or “approximately” as used herein is inclusive of the statedvalue and means within an acceptable range of deviation for theparticular value as determined by one of ordinary skill in the art,considering the measurement in question and the error associated withmeasurement of the particular quantity (i.e., the limitations of themeasurement system). For example, “about” can mean within one or morestandard deviations, or within±30%, 20%, 10%, 5% of the stated value.

According to an aspect, an organometallic compound is represented byFormula 1.

M₁(Ln₁)_(n1)(Ln₂)_(n2)   Formula 1

wherein, in Formula 1, M₁ is a transition metal.

In one or more embodiments, M₁ may be a first-row transition metal ofthe Periodic Table of Elements, a second-row transition metal of thePeriodic Table of Elements, or a third-row transition metal of thePeriodic Table of Elements.

In one or more embodiments, M₁ may be iridium (Ir), platinum (Pt),osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), thulium (Tm), or rhodium (Rh).

In one or more embodiments, M₁ may be Ir, Pt, Os, or Rh.

In one or more embodiments, M₁ may be Ir.

In Formula 1, n1 is 1 or 2, and n2 is 1, 2, or 3.

In one or more embodiments, a sum of n1 and n2 may be 2 or 3 (i.e.,n1+n2 may be 2 or 3).

In one or more embodiments, M₁ may be Ir, and a sum of n1 and n2 may be2 or 3 (i.e., n1+n2 may be 2 or 3).

In one or more embodiments, M₁ may be Pt, and a sum of n1 and n2 may be2 (i.e., n1+n2 may be 2).

In Formula 1, Ln₁ is a ligand represented by Formula 1A:

In Formula 1, Ln₂ is a ligand represented by Formula 1B:

In Formula 1A, X₁ is C or N, and X₂ is C or N.

In Formula 1A, CY₁ and CY₂ are each independently a C₅-C₃₀ carbocyclicgroup or a C₁-C₃₀ heterocyclic group.

In one or more embodiments, CY₁ may be i) a first ring, ii) a secondring, iii) a condensed ring in which at least two first rings arecondensed, iv) a condensed ring in which at least two second rings arecondensed, or v) a condensed ring in which at least one first ring andat least one second ring are condensed,

wherein the first ring may be a cyclopentane group, a cyclopentadienegroup, a furan group, a thiophene group, a pyrrole group, a silolegroup, an indene group, a benzofuran group, a benzothiophene group, anindole group, a benzosilole group, an oxazole group, an isoxazole group,an oxadiazole group, an isoxadiazole group, an oxatriazole group, anisoxatriazole group, a thiazole group, an isothiazole group, athiadiazole group, an iso-thiadiazole group, a thiatriazole group, anisothiatriazole group, a pyrazole group, an imidazole group, a triazolegroup, a tetrazole group, an azasilole group, a diazasilole group, or atriazasilole group, and

the second ring may be an adamantane group, a norbornane group, anorbornene group, a cyclohexane group, a cyclohexene group, a benzenegroup, a pyridine group, a pyrimidine group, a pyrazine group, apyridazine group, or a triazine group.

In one or more embodiments, CY₁ and CY₂ may each independently be acyclopentane group, a cyclohexane group, a cycloheptane group, acyclopentene group, a cyclohexene group, a cycloheptene group, a benzenegroup, a naphthalene group, an anthracene group, a phenanthrene group, atriphenylene group, a pyrene group, a chrysene group, a cyclopentadienegroup, a 1,2,3,4-tetrahydronaphthalene group, a thiophene group, a furangroup, an indole group, a benzoborole group, a benzophosphole group, anindene group, a benzosilole group, a benzogermole group, abenzothiophene group, a benzoselenophene group, a benzofuran group, acarbazole group, a dibenzoborole group, a dibenzophosphole group, afluorene group, a dibenzosilole group, a dibenzogermole group, adibenzothiophene group, a dibenzoselenophenegroup, a dibenzofuran group,a dibenzothiophene 5-oxide group, a 9H-fluoren-9-one group, adibenzothiophene 5,5-dioxide group, an azaindole group, anazabenzoborole group, an azabenzophosphole group, an azaindene group, anazabenzosilole group, an azabenzogermole group, an azabenzothiophenegroup, an azabenzoselenophene group, an azabenzofuran group, anazacarbazole group, an azadibenzoborole group, an azadibenzophospholegroup, an azafluorene group, an azadibenzosilole group, anazadibenzogermole group, an azadibenzothiophene group, anazadibenzoselenophene group, an azadibenzofuran group, anazadibenzothiophene 5-oxide group, an aza-9H-fluoren-9-one group, anazadibenzothiophene 5,5-dioxide group, a pyridine group, a pyrimidinegroup, a pyrazine group, a pyridazine group, a triazine group, aquinoline group, an isoquinoline group, a quinoxaline group, aquinazoline group, a phenanthroline group, a pyrrole group, a pyrazolegroup, an imidazole group, a triazole group, an oxazole group, anisooxazole group, a thiazole group, an isothiazole group, an oxadiazolegroup, a thiadiazole group, a benzopyrazole group, a benzimidazolegroup, a benzoxazole group, a benzothiazole group, a benzoxadiazolegroup, a benzothiadiazole group, a 5,6,7,8-tetrahydroisoquinoline group,or a 5,6,7,8-tetrahydroquinoline group.

In one or more embodiments, CY₁ and CY₂ may each independently be abenzene group, a naphthalene group, a 1,2,3,4-tetrahydronaphthalenegroup, a phenanthrene group, a pyridine group, a pyrimidine group, apyrazine group, a triazine group, a quinoline group, an isoquinolinegroup, a quinoxaline group, a quinazoline group, a phenanthroline group,a benzofuran group, a benzothiophene group, a fluorene group, acarbazole group, a dibenzofuran group, a dibenzothiophene group, adibenzosilole group, an azafluorene group, an azacarbazole group, anazadibenzofuran group, an azadibenzothiophene group, or anazadibenzosilole group.

In one or more embodiments, CY₁ may be a pyridine group, a pyrimidinegroup, a pyrazine group, a triazine group, a quinoline group, anisoquinoline group, a quinoxaline group, or a quinazoline group.

In one or more embodiments, CY₂ may be a benzene group, a naphthalenegroup, a pyridine group, a pyrimidine group, a pyrazine group, atriazine group, a quinoline group, an isoquinoline group, a quinoxalinegroup, a quinazoline group, a fluorene group, a carbazole group, adibenzofuran group, a dibenzothiophene group, or a dibenzosilole group.

In Formula 1B, CY₃ is a 6-membered N-containing heterocyclic group, a6-membered N-containing heterocyclic group condensed with a C₅-C₃₀carbocyclic group, or a 6-membered N-containing heterocyclic groupcondensed with a C₁-C₃₀ heterocyclic group.

In one or more embodiments, CY₃ may be a pyridine group, a pyrimidinegroup, a pyrazine group, a pyridazine group, a triazine group, aquinoline group, an isoquinoline group, a benzoquinoline group, abenzoisoquinoline group, a phenanthroline group, a quinoxaline group, ora quinazoline group.

In Formula 1B, CY₄₁ is a 5-membered carbocyclic group or a 5-memberedheterocyclic group.

In one or more embodiments, CY₄₁ may be a cyclopentadiene group, a furangroup, a thiophene group, a selenophene group, a pyrrole group, a borolegroup, an oxazole group, a thiazole group, a selenazole group, animidazole group, an azaborole group, an oxaborole group, a thiaborolegroup, a selenaborole group, or a diborole group.

In one or more embodiments, in Formula 1A, CY₁ may be represented by oneof Formulae 1-1 to 1-16:

wherein, in Formulae 1-1 to 1-16,

R₁₁ to R₁₄ may each independently be understood by referring to thedescription of R₁₀ provided herein, provided that R₁₁ to R₁₄ may noteach be hydrogen, and

* indicates a binding site to M₁, and

*′ indicates a binding site to an adjacent atom.

In one or more embodiments, in Formula 1A, CY₂ may be represented by oneof Formulae 2-1 to 2-16:

wherein, in Formulae 2-1 to 2-16,

R₂₁ to R₂₄ may each independently be understood by referring to thedescription of R₂₀ provided herein, provided that R₂₁ to R₂₄ may noteach be hydrogen, and

* indicates a binding site to M₁, and

*″ indicated a binding site to an adjacent atom.

In one or more embodiments, in Formula 1 B, CY₃ may be represented byone of Formulae 3-1 to 3-16:

wherein, in Formulae 3-1 to 3-16,

R₃₁ to R₃₄ may each independently be understood by referring to thedescription of R₃₀ provided herein, provided that R₃₁ to R₃₄ may noteach be hydrogen, and

* indicates a binding site to M₁, and

*′ indicates a binding site to an adjacent atom.

In Formula 1, R₁₀, R₂₀, R₃₀, and R₄₁ to R₅₀ are each independentlyhydrogen, deuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₁-C₆₀ alkylthiogroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₂-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₇-C₆₀alkyl aryl group, a substituted or unsubstituted C₇-C₆₀ aryl alkylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedC₂-C₆₀ alkyl heteroaryl group, a substituted or unsubstituted C₂-C₆₀heteroaryl alkyl group, a substituted or unsubstituted C₁-C₆₀heteroaryloxy group, a substituted or unsubstituted C₁-C₆₀heteroarylthio group, a substituted or unsubstituted monovalentnon-aromatic condensed polycyclic group, a substituted or unsubstitutedmonovalent non-aromatic condensed heteropolycyclic group, —N(Q₁)(Q₂),—Si(Q₃)(Q₄)(Q₅), —Ge(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), —P(Q₈)(Q₉), or—P(═O)(Q₈)(Q₉).

In Formula 1, b10, b20, and b30 are each independently 1 , 2, 3, 4, 5,6, 7, 8, 9, or 10.

In one or more embodiments, b10, b20, and b30 may each independently be1, 2, 3, 4, 5, 6, 7, or 8.

In one or more embodiments, b10, b20, and b30 may each independently be1, 2, 3, or 4.

In one or more embodiments, b10, b20, and b30 may each independently be1 or 2.

In one or more embodiments, b10, b20, and b30 may each independently be1.

In one or more embodiments, R₁₀, R₂₀, R₃₀, and R₄₀ to R₄₂ may eachindependently be:

hydrogen, deuterium, —F, —Cl, —Br, —I, —SF₅, —CD₃, —CD₂H, —CDH₂, —CF₃,—CF₂H, —CFH_(2,) a hydroxyl group, a cyano group, a nitro group, anamino group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, —SF₅, C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, or a C₁-C₂₀ alkylthio group;

a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, or a C₁-C₂₀ alkylthiogroup, each substituted with at least one of deuterium, —F, —Cl, —Br,—I, —SF₅, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, a phosphoric acidgroup or a salt thereof, a C₁-C₁₀ alkyl group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbomanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, abenzene group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbomanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a benzene group, a naphthyl group, a fluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a purinyl group, a qjinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a carbazolyl group, aphenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, abenzothiophenyl group, an isobenzolhiazolyl group, a benzoxazolyl group,an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, an imidazopyridinyl group, or an imidazopyrimidinyl group;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbomanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a benzene group, a naphthyl group, a fluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a purinyl group, a qjinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a carbazolyl group, aphenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, abenzothiophenyl group, an isobenzolhiazolyl group, a benzoxazolyl group,an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, an imidazopyridinyl group, or an imidazopyrimidinyl group, eachsubstituted with at least one of deuterium, —F, —Cl, —Br, —I, —SF₅,—CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group,a nitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a C₁-C₂₀ alkylthio group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, an adamantanyl group, a norbornanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, abenzene group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, an imidazopyrimidinyl group, or a combination thereof; or

—Si(Q₁)(Q₂)(Q₃), —Ge(Q₁)(Q₂)(Q₃), —N(Q₄)(Q₅), —B(Q₆)(Q₇), —P(Q₈)(Q₉), or—P(═O)(Q₈)(Q₉).

In one or more embodiments, R₁₀, R₂₀, R₃₀, and R₄₀ to R₄₂ may eachindependently be:

hydrogen, deuterium, —F, —Cl, —Br, —I, —SF₅, —CD₃, —CD₂H, —CDH₂, —CF₃,—CF₂H, —CFH₂, C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀ alkoxy group, or a C₁-C₂₀ alkylthio group; or

a group represented by one of Formulae 9-1 to 9-61, 9-201 to 9-237, 10-1to 10-129, or 10-201 to 10-350:

wherein, in Formulae 9-1 to 9-61, 9-201 to 9-237, 10-1 to 10-129, and10-201 to 10-350, * represents a binding site to an adjacent atom, “Ph”represents a benzene group, “TMS” represents a trimethylsilyl group, and“TMG” represents a trimethylgermyl group.

In Formulae 1A and 1B, two or more of a plurality of R₁₀(s); two or moreof a plurality of R₂₀(s); two or more of a plurality of R₃₀(s); and twoor more adjacent groups of R₁₀, R₂₀, and R₃₀ are optionally bondedtogether to form a substituted or unsubstituted C₅-C₃₀ carbocyclic groupor a substituted or unsubstituted C₁-C₃₀ heterocyclic group.

In one or more embodiments, two or more of a plurality of R₁₀(s); two ormore of a plurality of R₂₀(s); two or more of a plurality of R₃₀(s); andtwo or more adjacent groups of R₁₀, R₂₀, and R₃₀ may optionally bebonded together to form, via a single bond, a double bond, or a firstlinking group, a C₅-C₃₀ carbocyclic group unsubstituted or substitutedwith at least one R_(10a) or a C₁-C₃₀ heterocyclic group unsubstitutedor substituted with at least one R_(10a) (e.g., a fluorene group, axanthene group, or an acridine group, each unsubstituted or substitutedwith at least one R_(10a)). R_(10a) may be understood by referring tothe description of R₁₀ provided herein.

The first linking group may be *—N(R₈)—*′, *—B(R₈)—*′, *—P(R₈)—*′,*—C(R₈)(R₉)—*′, *—Si(R₈)(R₉)—*′, *—Ge(R₈)(R₉)—*′, *—S—*′, *—Se—*′,*—O—*′, *—C(═O)—*′, *—S(═O)—*′, *—S(═O)₂—*′, *—C(R₈)═*′, *═C(R₈)—*′,*—C(R₈)═C(R₉)—*′, *—C(═S)—*′, and *—CEC—*′, wherein R₈ and R₉ may eachbe understood by referring to the description of R₁₀ provided herein,and * and *′ may each be a binding site to an adjacent atom.

In one or more embodiments, Q₁ to Q₉, Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁ toQ₃₉ may each independently be:

deuterium, —CH₃, —CD₃, —CD₂H, —CDH₂, —CH₂CH₃, —CH₂CD₃, —CH₂CD₂H,—CH₂CDH₂, —CHDCH₃, —CHDCD₂H, —CHDCDH₂, —CHDCD₃, —CD₂CD₃, —CD₂CD₂H, or—CD₂CDH₂,

an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butylgroup, a sec-butyl group, a tert-butyl group, an n-pentyl group, aniso-pentyl group, a sec-pentyl group, a tert-pentyl group, a benzenegroup, or a naphthyl group; or

an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butylgroup, a sec-butyl group, a tent-butyl group, an n-pentyl group, aniso-pentyl group, a sec-pentyl group, a tent-pentyl group, a benzenegroup, or a naphthyl group, each substituted with at least one ofdeuterium, a C₁-C₁₀ alkyl group, a benzene group, or a combinationthereof.

In one or more embodiments, Ln₂ may be represented by Formula 21-1 orFormula 21-2:

wherein, in Formulae 21-1 and 21-2,

CY₃, R₃₀, R₄₁, R₄₂, and b30 may respectively be understood by referringto the descriptions of CY₃, R₃₀, R₄₁, R₄₂, and b30 provided herein,

X₄₁ may be N, B, or C(R₄₄),

X₄₂ may be O, S, Se, N(R₄₅), B(R₄₆), or C(R₄₅)(R₄₆),

R₄₃ to R₄₆ may each independently be understood by referring to thedescription of R₄₀ provided herein, and

* and *′ each indicate a binding site to M₁.

In one or more embodiments, the organometallic compound may be acompound represented by Formula 31-1 or Formula 31-2:

wherein, in Formulae 31-1 and 31-2,

M₁, n1, n2, R₄₁, and R₄₂ may respectively be understood by referring tothe descriptions of M₁, n1, n2, R₄₁, and R₄₂ provided herein,

X₁₁ may be C(R₁₁) or N, X₁₂ may be C(R₁₂) or N, X₁₃ may be C(R₁₃) or N,and X₁₄ may be C(R₁₄) or N,

X₂₁ may be C(R₂₁) or N, X₂₂ may be C(R₂₂) or N, X₂₃ may be C(R₂₃) or N,and X₂₄ may be C(R₂₄) or N,

X₃₁ may be C(R₃₁) or N, X₃₂ may be C(R₃₂) or N, X₃₃ may be C(R₃₃) or N,and X₃₄ may be C(R₃₄) or N,

X₄₁ may be N, B, or C(R₄₄),

X₄₂ may be O, S, Se, N(R₄₅), B(R₄₆), or C(R₄₅)(R₄₆),

R₁₁ to R₁₄ may each independently be understood by referring to thedescription of R₁₀ provided herein,

R₂₁ to R₂₄ may each independently be understood by referring to thedescription of R₂₀ provided herein,

R₃₁ to R₃₄ may each independently be understood by referring to thedescription of R₃₀ provided herein,

R₄₃ to R₄₆ may each independently be understood by referring to thedescription of R₄₀ provided herein,

at least two of R₁₁ to R₁₄ may optionally be bonded together to form aC₅-C₃₀ carbocyclic group unsubstituted or substituted with at least oneR_(10a) or a C₁-C₃₀ heterocyclic group unsubstituted or substituted withat least one R_(10a),

at least two of R₂₁ to R₂₄ may optionally be bonded together to form aC₅-C₃₀ carbocyclic group unsubstituted or substituted with at least oneR_(10a) or a C₁-C₃₀ heterocyclic group unsubstituted or substituted withat least one R_(10a),

at least two of R₃₁ to R₃₄ may optionally be bonded together to form aC₅-C₃₀ carbocyclic group unsubstituted or substituted with at least oneR_(10a) or a C₁-C₃₀ heterocyclic group unsubstituted or substituted withat least one R_(10a), and

R_(10a) may be understood by referring to the description of R₁₀provided herein.

In one or more embodiments, examples of the ″C₅-C₃₀ carbocyclic groupunsubstituted or substituted with at least one R_(10a) or C₁-C₃₀heterocyclic group unsubstituted or substituted with at least oneR_(10a)″ include a benzene group, a naphthalene group, a cyclopentanegroup, a cyclopentadiene group, a cyclohexane group, a cycloheptanegroup, a bicyclo[2.2.1]heptane group, a furan group, a thiophene group,a pyrrole group, a silole group, an indene group, a benzofuran group, abenzothiophene group, an indole group, or a benzosilole group, eachunsubstituted or substituted with at least one R_(10a). R_(10a) may beunderstood by referring to the description of R₁₀ provided herein. TheC₅-C₃₀ carbocyclic group and the C₁-C₃₀ heterocyclic group mayrespectively be understood by referring to the descriptions of theC₅-C₃₀ carbocyclic group and the C₁-C₃₀ heterocyclic group providedherein.

In one or more embodiments, at least one of R₁₀(s) in the number of b10,R₂₀(s) in the number of b20, R₃₀(s) in the number of b30, R₃₀(s) in thenumber of b40, R₄₁, and R₄₂ may be a methyl group, an ethyl group, ann-propyl group, an iso-propyl group, an n-butyl group, an isobutylgroup, a sec-butyl group, a tent-butyl group, an n-pentyl group, anisopentyl group, a 2-methylbutyl group, a sec-pentyl group, atert-pentyl group, a neo-pentyl group, a 3-pentyl group, a3-methyl-2-butyl group, a cyclopropyl group, a cyclobutyl group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, a benzene group, a biphenyl group, a C₁-C₂₀ alkylphenyl group, anaphthyl group, —Si(Q₁)(Q₂)(Q₃), or —Ge(Q₁)(Q₂)(Q₃), each unsubstitutedor substituted with deuterium.

In one or more embodiments, the ligand represented by Formula 1A mayinclude a silyl group ora germyl group, and the ligand represented byFormula 1B may not include a silyl group or a germyl group.

In one or more embodiments, the organometallic compound may berepresented by one or more of Compounds 1 to 132:

In one or more embodiments, the organometallic compound may beelectrically neutral.

The organometallic compound represented by Formula 1 may satisfy Formula1, and the ligand represented by Formula 1B may include a benzene group,to which CY₄₁, which is a 5-membered carbocyclic group or a 5-memberedheterocyclic group, is condensed. Due to this structure, theorganometallic compound represented by Formula 1 may have improvedemission characteristics. In particular, the organometallic compound mayhave suitable characteristics for use in high colorimetric purityemission material by controlling emission wavelength.

In addition, the organometallic compound represented by Formula 1 mayhave excellent electrical mobility. Thus, an electronic device includingthe organometallic compound, e.g., an organic light-emitting device mayhave a low driving voltage, high efficiency, long lifespan, and reducedoccurrence of roll-off.

In addition, the organometallic compound represented by Formula 1 mayhave improved photochemical stability. Thus, and electronic device,e.g., an organic light-emitting device, including the organometalliccompound may have improved emission efficiency, lifespan, andcolorimetric purity.

The highest occupied molecular orbital (HOMO) energy level, lowestunoccupied molecular orbital (LUMO) energy level, lowest singlet (S₁)energy level, and lowest triplet (T₁) energy level of organometalliccompounds represented by Formula 1 were evaluated by density functionaltheory (DFT) using Gaussian 09 that performs molecular structureoptimizations at a degree of B3LYP. The results thereof are shown inTable 1, where the energy levels are reported as electron Volts (eV).

TABLE 1 HOMO LUMO S₁ T₁ Compound (eV) (eV) (eV) (eV) Compound 1 −4.857−1.365 2.859 2.420 Compound 25 −4.798 −1.199 2.862 2.573

Referring to the results of Table 1, the organometallic compoundrepresented by Formula 1 was found to have suitable electricalcharacteristics for use as a dopant in an electronic device, e.g., anorganic light-emitting device.

In one or more embodiments, a full width at half maximum (FWHM, nm) inthe photoluminescence (PL) spectrum and/or electroluminescence (EL)spectrum of the organometallic compound may be 70 nanometers (nm) orless. For example, a FWHM in the PL spectrum and/or EL spectrum of theorganometallic compound may be in a range of about 30 nm to about 65 nm,about 40 nm to about 63 nm, or about 45 nm to about 62 nm.

A maximum emission wavelength (emission peak maximum wavelength,λ_(max)) in the photoluminescence spectrum or electroluminescencespectrum of the organometallic compound may be in a range of about 490nm to about 550 nm.

A method of synthesizing the organometallic compound represented byFormula 1 may be apparent to one of ordinary skill in the art byreferring to Synthesis Examples provided herein.

The organometallic compound represented by Formula 1 may be suitable foruse in an organic layer of an organic light-emitting device, e.g., as adopant in an emission layer of the organic layer. Thus, according toanother aspect, there is provided an organic light-emitting device thatmay include a first electrode; a second electrode; and an organic layerbetween the first electrode and the second electrode, wherein theorganic layer includes an emission layer and at least one organometalliccompound represented by Formula 1.

As the organic light-emitting device may include an organic layerincluding the organometallic compound represented by Formula 1, theorganic light-emitting device may have excellent driving voltage,current efficiency, power efficiency, external quantum yield, lifespan,and/or colorimetric purity characteristics. In addition, occurrence ofroll-off may be reduced, and thus, a relatively narrow FWHM in the ELspectrum emission peak may be shown.

The organometallic compound represented by Formula 1 may be used in apair of electrodes of an organic light-emitting device. For example, theorganometallic compound represented by Formula 1 may be included in theemission layer. In this embodiment, the organometallic compound mayserve as a dopant and the emission layer may further include a host(that is, an amount of the organometallic compound represented byFormula 1 may be smaller than that of the host in the emission layer).

In one or more embodiments, the emission layer may emit green light. Inone or more embodiments, the emission layer may emit green light havinga maximum emission wavelength in a range of about 490 nm to about 550nm.

As used herein, “(for example, the organic layer) including at least oneorganometallic compound” means that “(the organic layer) including anorganometallic compound of Formula 1, or at least two differentorganometallic compounds of Formula 1”.

For example, Compound 1 may only be included in the organic layer as anorganometallic compound. In this embodiment, Compound 1 may be includedin the emission layer of the organic light-emitting device. In one ormore embodiments, Compounds 1 and 2 may be included in the organic layeras organometallic compounds. In this embodiment, Compounds 1 and 2 mayboth be included in the same layer (for example, both Compounds 1 and 2may be included in the emission layer).

The first electrode may be an anode, which is a hole injectionelectrode, and the second electrode may be a cathode, which is anelectron injection electrode. In one or more embodiments, the firstelectrode may be a cathode, which is an electron injection electrode,and the second electrode may be an anode, which is a hole injectionelectrode.

For example, in the organic light-emitting device, the first electrodemay be an anode, the second electrode may be a cathode, and the organiclayer may further include a hole transport region between the firstelectrode and the emission layer and an electron transport regionbetween the emission layer and the second electrode, wherein the holetransport region may include a hole injection layer, a hole transportlayer, an electron blocking layer, a buffer layer, or a combinationthereof, and the electron transport region may include a hole blockinglayer, an electron transport layer, an electron injection layer, or acombination thereof.

The term “organic layer” as used herein refers to a single and/or aplurality of layers between the first electrode and the second electrodein an organic light-emitting device. The “organic layer” may include notonly organic compounds but also organometallic complexes includingmetals.

The FIGURE illustrates a schematic cross-sectional view of an organiclight-emitting device 10 according to one or more embodiments.Hereinafter, a structure of an organic light-emitting device accordingto one or more embodiments and a method of manufacturing the organiclight-emitting device will be described with reference to the FIGURE.The organic light-emitting device 10 may include a first electrode 11,an organic layer 15, and a second electrode 19, which may besequentially layered in this stated order.

A substrate may be additionally disposed under the first electrode 11 oron the second electrode 19. The substrate may be a conventionalsubstrate used in organic light-emitting devices, e.g., a glasssubstrate or a transparent plastic substrate, each having excellentmechanical strength, thermal stability, transparency, surfacesmoothness, ease of handling, and/or water repellency.

The first electrode 11 may be produced by depositing or sputtering, ontothe substrate, a material for forming the first electrode 11. The firstelectrode 11 may be an anode. The material for forming the firstelectrode 11 may be selected from materials with a high work functionfor easy hole injection. The first electrode 11 may be a reflectiveelectrode, a semi-transmissive electrode, or a transmissive electrode.The material for forming the first electrode 11 may be indium tin oxide(ITO), indium zinc oxide (IZO), tin oxide (SnO₂), or zinc oxide (ZnO).In one or more embodiments, the material for forming the first electrode11 may be a metal, such as magnesium (Mg), aluminum (Al), silver (Ag),aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), ormagnesium-silver (Mg—Ag).

The first electrode 11 may have a single-layered structure or amulti-layered structure including a plurality of layers. In one or moreembodiments, the first electrode 11 may have a triple-layered structureof ITO/Ag/ITO, but embodiments are not limited thereto.

The organic layer 15 may be disposed on or located on the firstelectrode 11.

The organic layer 15 may include a hole transport region, an emissionlayer, and an electron transport region.

The hole transport region may be located between the first electrode 11and the emission layer.

The hole transport region may include a hole injection layer, a holetransport layer, an electron blocking layer, a buffer layer, or acombination thereof.

The hole transport region may include a hole injection layer only, or ahole transport layer only. In one or more embodiments, the holetransport region may include a hole injection layer and a hole transportlayer which are sequentially stacked on the first electrode 11. In oneor more embodiments, the hole transport region may include a holeinjection layer, a hole transport layer, and an electron blocking layer,which are sequentially stacked on the first electrode 11.

When the hole transport region includes a hole injection layer, the holeinjection layer may be formed on the first electrode 11 by using one ormore suitable methods, such as vacuum deposition, spin coating, casting,and Langmuir-Blodgett (LB) deposition.

When a hole injection layer is formed by vacuum deposition, for example,the vacuum deposition may be performed at a deposition temperature in arange of about 100° C. to about 500° C., at a vacuum degree in a rangeof about 10⁻⁸ torr to about 10⁻³ torr, and at a deposition rate in arange of about 0.01 Angstroms per second (Å/sec) to about 100 Å/sec,though the conditions may vary depending on a compound that is used as ahole injection material and a structure and thermal properties of adesired hole injection layer, but conditions for the vacuum depositionare not limited thereto.

When a hole injection layer is formed by spin coating, the spin coatingmay be performed at a coating rate in a range of about 2,000 revolutionsper minute (rpm) to about 5,000 rpm, and at a temperature in a range ofabout 80° C. to 200° C., to facilitate removal of a solvent after thespin coating, though the conditions may vary depending on a compoundthat is used as a hole injection material and a structure and thermalproperties of a desired hole injection layer, but conditions for thespin coating are not limited thereto.

The conditions for forming a hole transport layer and an electronblocking layer may be inferred from the conditions for forming the holeinjection layer.

The hole transport region may include at least one of4,4′,4″-tris(3-methylphenylphenylarnino)triphenylarnine (m-MTDATA),4,4′,4″-tris(N,N-diphenylamino)triphenylamine (TDATA),4,4′,4″-tris{N-(2-naphthyl)-N-phenylamino}-triphenylamine (2-TNATA),N,N′-di(1-naphthyl)-N,N¹-diphenylbenzidine (NPB), β-NPB,N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1-biphenyl]-4,4′-diamine(TPD), spiro-TPD, spiro-NPB, methylated NPB, 4,4′-cyclohexylidenebis[N,N-bis(4-methylphenyl)benzenamine] (TAPC),4,4′-bis[N,N′-(3-tolyl)amino]-3,3′-dimethylbiphenyl (HMTPD),4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA),poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS),polyaniline/camphor sulfonic acid (PANI/CSA),(polyaniline)/poly(4-styrenesulfonate) (PANI/PSS), a compoundrepresented by Formula 201, a compound represented by Formula 202, or acombination thereof:

wherein, in Formula 201, Ar₁₀₁ and Ar₁₀₂ may each independently be:

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anacenaphthylene group, a fluorenylene group, a phenalenylene group, aphenanthrenylene group, an anthracenylene group, a fluoranthenylenegroup, a triphenylenylene group, a pyrenylene group, a chrysenylenylenegroup, a naphthacenylene group, a picenylene group, a perylenylenegroup, or a pentacenylene group; or

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anacenaphthylene group, a fluorenylene group, a phenalenylene group, aphenanthrenylene group, an anthracenylene group, a fluoranthenylenegroup, a triphenylenylene group, a pyrenylene group, a chrysenylenylenegroup, a naphthacenylene group, a picenylene group, a perylenylenegroup, or a pentacenylene group, each substituted with at least one ofdeuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a C₁-C₆₀ alkylthio group, a C₃-C₁₀ cycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₇-C₆₀ alkylaryl group, a C₇-C₆₀ aryl alkyl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀ heteroaryl group, a C₂-C₆₀ alkyl heteroarylgroup, a C₂-C₆₀ heteroaryl alkyl group, a C₁-C₆₀ heteroaryloxy group, aC₁-C₆₀ heteroarylthio group, a monovalent non-aromatic condensedpolycyclic group, a monovalent non-aromatic condensed heteropolycyclicgroup, or a combination thereof.

In Formula 201, xa and xb may each independently be an integer from 0 to5. In one or more embodiments, xa and xb may each independently be 0, 1,or 2. In one or more embodiments, xa may be 1, and xb may be 0, butembodiments are not limited thereto.

In Formulae 201 and 202, R₁₀₁ to R₁₀₈, R₁₁₁ to R₁₁₉, and R₁₂₁ to R₁₂₄may each independently be:

hydrogen, deuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, a C₁-C₁₀ alkyl group (e.g., a methyl group, an ethyl group, apropyl group, a butyl group, pentyl group, or a hexyl group), a C₁-C₁₀alkoxy group (e.g., a methoxy group, an ethoxy group, a propoxy group, abutoxy group, ora pentoxy group), or a C₁-C₁₀ alkylthio group;

a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, or a C₁-C₁₀ alkylthiogroup, each substituted with at least one of deuterium, —F, —Cl, —Br,—I, —SF₅, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, or a combinationthereof;

a benzene group, a naphthyl group, an anthracenyl group, a fluorenylgroup, or a pyrenyl group; or

a benzene group, a naphthyl group, an anthracenyl group, a fluorenylgroup, or a pyrenyl group, each substituted with at least one ofdeuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, C₁-C₁₀ alkylthio group, ora combination thereof, but embodiments are not limited thereto.

In Formula 201, R₁₀₉ may be:

a benzene group, a naphthyl group, an anthracenyl group, or a pyridinylgroup; or

a benzene group, a naphthyl group, an anthracenyl group, or a pyridinylgroup, each substituted with at least one of deuterium, —F, —Cl, —Br,—I, —SF₅, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a C₁-C₂₀ alkylthio group, a benzene group,a naphthyl group, an anthracenyl group, or a pyridinyl group.

In one or more embodiments, the compound represented by Formula 201 maybe represented by Formula 201A, but embodiments are not limited thereto:

wherein, in Formula 201A, R₁₀₁, R₁₁₁, R₁₁₂, and R₁₀₉ may respectively beunderstood by referring to the descriptions of R₁₀₁, R₁₁₁, R₁₁₂, andR₁₀₉ provided herein.

In one or more embodiments, the compounds represented by Formulae 201and 202 may include one or more of Compounds HT1 to HT20, butembodiments are not limited thereto:

The thickness of the hole transport region may be in a range of about100 Angstroms (Å) to about 10,000 Å, and in one or more embodiments,about 100 Å to about 1,000 Å. When the hole transport region includes atleast one of a hole injection layer and a hole transport layer, thethickness of the hole injection layer may be in a range of about 100 Åto about 10,000 Å, and in one or more embodiments, about 100 Å to about1,000 Å, and the thickness of the hole transport layer may be in a rangeof about 50 Å to about 2,000 Å, and in one or more embodiments, about100 Å to about 1,500 Å. When the thicknesses of the hole transportregion, the hole injection layer, and the hole transport layer arewithin any of these ranges, excellent hole transport characteristics maybe obtained without a substantial increase in driving voltage.

The hole transport region may include a charge generating material aswell as the aforementioned materials, to improve conductive propertiesof the hole transport region. The charge generating material may besubstantially homogeneously or non-homogeneously dispersed in the holetransport region.

The charge generating material may include, for example, a p-dopant. Thep-dopant may include one of a quinone derivative, a metal oxide, and acompound containing a cyano group, but embodiments are not limitedthereto. For example, non-limiting examples of the p-dopant include aquinone derivative, such as tetracyanoquinodimethane (TCNQ) or2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinonedimethane (F4-TCNQ); ametal oxide, such as a tungsten oxide or a molybdenum oxide; or acompound containing a cyano group, such as Compound HT-D1 or CompoundF12, but embodiments are not limited thereto:

The hole transport region may further include a buffer layer.

The buffer layer may compensate for an optical resonance distancedepending on a wavelength of light emitted from the emission layer toimprove the efficiency of an organic light-emitting device.

An emission layer may be formed on the hole transport region by usingone or more suitable methods, such as vacuum deposition, spin coating,casting, or LB deposition. When the emission layer is formed by vacuumdeposition or spin coating, vacuum deposition and coating conditions forforming the emission layer may be generally similar to those conditionsfor forming a hole injection layer, though the conditions may varydepending on a compound that is used.

When the hole transport region includes an electron blocking layer, amaterial for forming the electron blocking layer may be selected fromthe materials for forming a hole transport region and host materialsdescribed herein, but embodiments are not limited thereto. In one ormore embodiments, when the hole transport region includes an electronblocking layer, mCP described herein may be used for forming theelectron blocking layer.

The emission layer may include a host and a dopant, and the dopant mayinclude the organometallic compound represented by Formula 1.

The host may include at least one of1,3,5-tris(N-phenylbenzimidazole-2-yl)benzene (TP Bi),3-tert-butyl-9,10-di(naphth-2-yl)anthracene (TBADN),9,10-di(naphthalene-2-yl)anthracene (ADN, also known as “DNA”),4,4′-bis(N-carbazolyI)-1,1′-biphenyl (CBP),4,4′-bis(9-carbazolyl)-2,2′-dimethyl-biphenyl (CDBP), N,N′N″-1,3,5-tricarbazoloylbenzene (TCP), 1,3-bis(carbazol-9-yl)benzene (mCP),Compound H50, Compound H51, or a combination thereof:

In one or more embodiments, the host may further include a compoundrepresented by Formula 301:

wherein, in Formula 301, Ar₁₁₁ and Ar₁₁₂ may each independently be:

a phenylene group, a naphthylene group, a phenanthrenylene group, or apyrenylene group; or

a phenylene group, a naphthylene group, a phenanthrenylene group, or apyrenylene group, each substituted with at least one of a benzene group,a naphthyl group, an anthracenyl group, or a combination thereof.

In Formula 301, Ar₁₁₃ to Ar₁₁₆ may each independently be:

a C₁-C₁₀ alkyl group, a benzene group, a naphthyl group, a phenanthrenylgroup, or a pyrenyl group; or

a benzene group, a naphthyl group, a phenanthrenyl group, or a pyrenylgroup, each substituted with at least one of a benzene group, a naphthylgroup, an anthracenyl group, or a combination thereof.

In Formula 301, g, h, i, and j may each independently be an integer from0 to 4. In one or more embodiments, g, h, i, and j may eachindependently be 0, 1, or 2.

In Formula 301, Ar₁₁₃ to Ar₁₁₆ may each independently be:

a C₁-C₁₀ alkyl group substituted with at least one of a benzene group, anaphthyl group, an anthracenyl group, or a combination thereof;

a benzene group, a naphthyl group, an anthracenyl group, a pyrenylgroup, a phenanthrenyl group, or a fluorenyl group;

a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group,a phenanthrenyl group, or a fluorenyl group, each substituted with atleast one of deuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, a phosphoric acidgroup or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₁-C₆₀ alkylthio group, aphenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, aphenanthrenyl group, a fluorenyl group, or a combination thereof; or

a moiety represented by:

In one or more embodiments, the host may include a compound representedby Formula 302:

In Formula 302, Ar₁₂₂ to Ar₁₂₅ may each be understood by referring tothe description of Ar₁₁₃ in Formula 301.

In Formula 302, Ar₁₂₆ and Ar₁₂₇ may each independently be a C₁-C₁₀ alkylgroup, e.g., a methyl group, an ethyl group, or a propyl group.

In Formula 302, k and l may each independently be an integer from 0 to4. In one or more embodiments, k and l may each be 0, 1, or 2.

When the organic light-emitting device 10 is a full-color organiclight-emitting device, the emission layer may be patterned into a redemission layer, a green emission layer, and a blue emission layer. Inone or more embodiments, the emission layer may have a structure inwhich the red emission layer, the green emission layer, and/or the blueemission layer are layered to emit white light. In one or moreembodiments, the structure of the emission layer may vary.

When the emission layer includes the host and the dopant, an amount ofthe dopant may be from a range of about 0.01 parts to about 15 parts byweight based on about 100 parts by weight of the host, but embodimentsare not limited thereto.

The thickness of the emission layer may be in a range of about 100 Å toabout 1,000 Å, and in one or more embodiments, about 200 Å to about 600Å. When the thickness of the emission layer is within any of theseranges, improved luminescence characteristics may be obtained without asubstantial increase in driving voltage.

Next, an electron transport region may be formed on the emission layer.

The electron transport region may include a hole blocking layer, anelectron transport layer, an electron injection layer, or a combinationthereof.

In one or more embodiments, the electron transport region may have ahole blocking layer/an electron transport layer/an electron injectionlayer structure or an electron transport layer/an electron injectionlayer structure, but embodiments are not limited thereto. The electrontransport layer may have a single-layered structure or a multi-layeredstructure including two or more different materials.

The conditions for forming a hole blocking layer, an electron transportlayer, and an electron injection layer may be inferred based on theconditions for forming the hole injection layer.

When the electron transport region includes a hole blocking layer, thehole blocking layer may include, for example, at least one of2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP),4,7-diphenyl-1,10-phenanthroline (Bphen), orbis(2-methyl-8-quinolinolato-N1,08)-(1,1′-biphenyl-4-olato)aluminum(BAlq), but embodiments are not limited thereto:

The thickness of the hole blocking layer may be in a range of about 20 Åto about 1,000 Å, and in one or more embodiments, about 30 Å to about300 Å. When the thickness of the hole blocking layer is within any ofthese ranges, excellent hole blocking characteristics may be obtainedwithout a substantial increase in driving voltage.

The electron transport layer may further include at least one of BCP,Bphen, tris(8-hydroxyquinolinato)aluminum (Alq₃), BAlq,3-(4-biphenylyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), and4-(naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ):

In one or more embodiments, the electron transport layer may include atleast one of Compounds ET1 to ET25, but embodiments are not limitedthereto:

The thickness of the electron transport layer may be in a range of about100 Å to about 1,000 Å, and in one or more embodiments, about 150 Å toabout 500 Å. When the thickness of the electron transport layer iswithin any of these ranges, excellent electron transport characteristicsmay be obtained without a substantial increase in driving voltage.

The electron transport layer may further include a material containingmetal, in addition to the materials described above.

The material containing metal may include a Li complex. The Li complexmay include, e.g., Compound ET-D1 (LiQ) or Compound ET-D2

The electron transport region may include an electron injection layerthat facilitates electron injection from the second electrode 19.

The electron injection layer may include at least one of LiF, NaCl, CsF,Li₂O, BaO, or a combination thereof.

The thickness of the electron injection layer may be in a range of about1 Å to about 100 Å, for example, about 3 Å to about 90 Å. When thethickness of the electron injection layer is within any of these ranges,excellent electron injection characteristics may be obtained without asubstantial increase in driving voltage.

The second electrode 19 may be on the organic layer 15. The secondelectrode 19 may be a cathode. A material for forming the secondelectrode 19 may be a material with a relatively low work function, suchas a metal, an alloy, an electrically conductive compound, and a mixturethereof. Examples of the material for forming the second electrode 19may include lithium (Li), magnesium (Mg), aluminum (Al), silver (Ag),aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), andmagnesium-silver (Mg—Ag). In one or more embodiments, ITO or IZO may beused to form a transmissive second electrode 19 to manufacture a topemission light-emitting device. In one or more embodiments, the materialfor forming the second electrode 19 may vary.

Hereinbefore the organic light-emitting device 10 has been describedwith reference to the FIGURE, but embodiments are not limited thereto.

According to another aspect, a diagnostic composition may include atleast one organometallic compound represented by Formula 1.

Since the organometallic compound represented by Formula 1 provides highluminescence efficiency, the diagnostic efficiency of the diagnosticcomposition that includes the organometallic compound represented byFormula 1 may be excellent.

The diagnostic composition may be applied in various ways, such as in adiagnostic kit, a diagnostic reagent, a biosensor, or a biomarker.

The term “C₁-C₆₀ alkyl group” as used herein refers to a linear orbranched saturated aliphatic hydrocarbon monovalent group having 1 to 60carbon atoms. Examples thereof include a methyl group, an ethyl group, apropyl group, an iso-butyl group, a sec-butyl group, a tert-butyl group,a pentyl group, an iso-amyl group, and a hexyl group. The term “C₁-C₆₀alkylene group” as used herein refers to a divalent group having thesame structure as the C₁-C₆₀ alkyl group.

The term “C₁-C₆₀ alkoxy group” as used herein refers to a monovalentgroup represented by —OA₁₀₁ (wherein A₁₀₁ is a C₁-C₆₀ alkyl group).Examples thereof include a methoxy group, an ethoxy group, and anisopropyloxy group.

The term “C₁-C₆₀ alkylthio group” as used herein refers to a monovalentgroup represented by —SA_(101′) (wherein A_(101′) is a C₁-C₆₀ alkylgroup).

The term “C₂-C₆₀ alkenyl group” as used herein refers to a group formedby including at least one carbon-carbon double bond in the middle or atthe terminus of the C₂-C₆₀ alkyl group. Examples thereof include anethenyl group, a propenyl group, and a butenyl group. The term “C₂-C₆₀alkenylene group” as used herein refers to a divalent group having thesame structure as the C₂-C₆₀ alkenyl group.

The term “C₂-C₆₀ alkynyl group” as used herein refers to a group formedby including at least one carbon-carbon triple bond in the middle or atthe terminus of the C₂-C₆₀ alkyl group. Examples thereof include anethenyl group and a propenyl group. The term “C₂-C₆₀ alkynylene group”as used herein refers to a divalent group having the same structure asthe C₂-C₆₀ alkynyl group.

The term “C₃-C₁₀ cycloalkyl group” as used herein refers to a monovalentmonocyclic saturated hydrocarbon group including 3 to 10 carbon atoms.Examples thereof include a cyclopropyl group, a cyclobutyl group, acyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The term“C₃-C₁₀ cycloalkylene group” as used herein refers to a divalent grouphaving the same structure as the C₃-C₁₀ cycloalkyl group.

The term “C₁-C₁₀ heterocycloalkyl group” as used herein refers to amonovalent monocyclic group including at least one heteroatom selectedfrom N, O, P, Si, Ge, Se, and S as a ring-forming atom(s) and 1 to 10carbon atoms as ring forming atom(s). Examples thereof include atetrahydrofuranyl group and a tetrahydrothiophenyl group. The term“C₁-C₁₀ heterocycloalkylene group” as used herein refers to a divalentgroup having the same structure as the C₁-C₁₀ heterocycloalkyl group.

The term “C₃-C₁₀ cycloalkenyl group” as used herein refers to amonovalent monocyclic group including 3 to 10 carbon atoms and at leastone carbon-carbon double bond in its ring, wherein the molecularstructure as a whole is non-aromatic. Examples thereof include acyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group.The term “C₃-C₁₀ cycloalkenylene group” as used herein refers to adivalent group having the same structure as the C₃-C₁₀ cycloalkenylgroup.

The term “C₂-C₁₀ heterocycloalkenyl group” as used herein refers to amonovalent monocyclic group including at least one heteroatom selectedfrom N, O, P, Si, Ge, Se, and S as a ring-forming atom(s), 2 to 10carbon atoms as ring forming atoms, and at least one double bond in itsring. Examples of the C₁-C₁₀ heterocycloalkenyl group include a2,3-dihydrofuranyl group and a 2,3-dihydrothiophenyl group. The term“C₂-C₁₀ heterocycloalkylene group” as used herein refers to a divalentgroup having the same structure as the C₂-C₁₀ heterocycloalkenyl group.

The term “C₆-C₆₀ aryl group” as used herein refers to a monovalent grouphaving a carbocyclic aromatic system having 6 to 60 carbon atoms only.The term “C₆-C₆₀ arylene group” as used herein refers to a divalentgroup having a carbocyclic aromatic system having 6 to 60 carbon atomsonly. Examples of the C₆-C₆₀ aryl group include a benzene group, anaphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenylgroup, and a chrysenyl group. When the C₆-C₆₀ aryl group and a C₆-C₆₀arylene group each include at least two rings, the at least two ringsmay be fused.

The term “C₇-C₆₀ alkyl aryl group” as used herein refers to a C₆-C₆₀aryl group substituted with at least one C₁-C₆₀ alkyl group. The term“C₇-C₆₀ aryl alkyl group” as used herein refers to a C₁-C₆₀ alkyl groupsubstituted with at least one C₆-C₆₀ aryl group.

The term “C₁-C₆₀ heteroaryl group” as used herein refers to a monovalentgroup having a heterocyclic aromatic system having at least oneheteroatom of N, O, P, and S as a ring-forming atom(s) and 1 to 60carbon atom(s) as ring-forming atoms. The term “C₁-C₆₀ heteroarylenegroup” as used herein refers to a divalent group having a heterocyclicaromatic system having at least one heteroatom of N, O, P, Si, and S asa ring-forming atom(s) and 1 to 60 carbon atom(s) as ring-forming atoms.Examples of the C₁-C₆₀ heteroaryl group include a pyridinyl group, apyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, and an isoquinolinyl group. When the C₁-C₆₀heteroaryl group and the C₁-C₆₀ heteroarylene group each include atleast two rings, the at least two rings may be fused.

The term “C₂-C₆₀ alkyl heteroaryl group” as used herein refers to aC₁-C₆₀ heteroaryl group substituted with at least one C₁-C₆₀ alkylgroup. The term “C₂-C₆₀ heteroaryl alkyl group” as used herein refers toa C₁-C₆₀ alkyl group substituted with at least one C₁-C₆₀ heteroarylgroup.

The term “C₆-C₆₀ aryloxy group” as used herein refers to —OA₁₀₂ (whereinA₁₀₂ is a C₆-C₆₀ aryl group). The term “C₆-C₆₀ arylthio group” as usedherein refers to —SA₁₀₃ (wherein A₁₀₃ is a C₆-C₆₀ aryl group).

The term “C₁-C₆₀ heteroaryloxy group” as used herein indicates —OA₁₀₄(wherein A₁₀₄ is a C₁-C₆₀ heteroaryl group). The term “C₁-C₆₀heteroarylthio group” as used herein indicates —SA₁₀₅ (wherein A₁₀₅ is aC₁-C₆₀ heteroaryl group).

The term “monovalent non-aromatic condensed polycyclic group” as usedherein refers to a monovalent group that has two or more condensed ringsand only carbon atoms (e.g., the number of carbon atoms may be in arange of 8 to 60) as ring-forming atoms, wherein the molecular structureas a whole is non-aromatic. Examples of the monovalent non-aromaticcondensed polycyclic group include a fluorenyl group. The term “divalentnon-aromatic condensed polycyclic group” as used herein refers to adivalent group having substantially the same structure as the monovalentnon-aromatic condensed polycyclic group.

The term “monovalent non-aromatic condensed heteropolycyclic group” asused herein refers to a monovalent group that has two or more condensedrings and a at least one heteroatom selected from N, O, P, Si, Se, Ge,and S as a ring forming atom(s) and carbon atoms (e.g., the number ofcarbon atoms may be in a range of 1 to 60) as ring-forming atoms,wherein the molecular structure as a whole is non-aromatic. Examples ofthe monovalent non-aromatic condensed heteropolycyclic group include acarbazolyl group. The term “divalent non-aromatic condensedheteropolycyclic group” as used herein refers to a divalent group havingthe same structure as the monovalent non-aromatic condensedheteropolycyclic group.

The term “C₅-C₃₀ carbocyclic group” as used herein refers to a saturatedor unsaturated cyclic group including 5 to 30 carbon atoms only asring-forming atoms. The C₅-C₃₀ carbocyclic group may be a monocyclicgroup or a polycyclic group.

The term “C₁-C₃₀ heterocyclic group” as used herein refers to saturatedor unsaturated cyclic group including at least one heteroatom selectedfrom N, O, P, Si, Se, Ge, and S as a ring-forming atom(s) and 1 to 30carbon atom(s) as ring-forming atom(s). The C₁-C₃₀ heterocyclic groupmay be a monocyclic group or a polycyclic group.

The term “TMS” as used herein represents *—Si(CH₃)₃, and the term “TMG”as used herein represents *—Ge(CH₃)₃.

At least one substituent of the substituted C₅-C₃₀ carbocyclic group,the substituted C₁-C₃₀ heterocyclic group, the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₁-C₆₀ alkylthio group, the substituted C₃-C₁₀ cycloalkyl group, thesubstituted C₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenyl group, thesubstituted C₆-C₆₀ aryl group, the substituted C₇-C₆₀ alkyl aryl group,the substituted C₇-C₆₀ aryl alkyl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted C₂-C₆₀ alkyl heteroaryl group, thesubstituted C₂-C₆₀ heteroaryl alkyl group, the substituted C₁-C₆₀heteroaryloxy group, the substituted C₁-C₆₀ heteroarylthio group, thesubstituted monovalent non-aromatic condensed polycyclic group, and thesubstituted monovalent non-aromatic condensed heteropolycyclic group maybe:

deuterium, —F, —Cl, —Br, —I, —SF₅, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid group or a salt thereof, a sulfonic acid group or a salt thereof, aphosphoric acid group or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, or aC₁-C₆₀ alkylthio group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, or a C₁-C₆₀ alkylthio group, each substituted withat least one of deuterium, —F, —Cl, —Br, —I, —SF₅, —CD₃, —CD₂H, —CDH₂,—CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitro group, anamino group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₇-C₆₀ alkylaryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a C₂-C₆₀ alkyl heteroaryl group, a C₁-C₆₀heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃),—Ge(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₄)(Q₁₅),—B(Q₁₆)(Q₁₇), —P(═O)(Q₁₈)(Q₁₉), or acombination thereof;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₇-C₆₀ alkyl aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀ heteroaryl group, a C₂-C₆₀ alkyl heteroarylgroup, a C₁-C₆₀ heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, amonovalent non-aromatic condensed polycyclic group, or a monovalentnon-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₇-C₆₀ alkyl aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀ heteroaryl group, a C₂-C₆₀ alkyl heteroarylgroup, a C₁-C₆₀ heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, amonovalent non-aromatic condensed polycyclic group, or a monovalentnon-aromatic condensed heteropolycyclic group, each substituted with atleast one of deuterium, —F, —Cl, —Br, —I, —SF₅, —CD₃, —CD₂H, —CDH₂,—CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitro group, anamino group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, a C₁-C₆₀ alkylthio group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₇-C₆₀ alkyl arylgroup, a C₇-C₆₀ aryl alkyl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀ heteroaryl group, a C₂-C₆₀ alkyl heteroarylgroup, a C₁-C₆₀ heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—Ge(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₄)(Q₂₅), —B(Q₂₆)(Q₂₇), —P(Q₂₈)(Q₂₉),—P(═O)(Q₂₈)(Q₂₉), or a combination thereof; or

—Si(Q₃₁)(Q₃₂)(Q₃₃), —Ge(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₄)(Q₃₅), —B(Q₃₆)(Q₃₇),—P(Q₃₈)(Q₃₉), or —P(═O)(Q₃₈)(Q₃₉),

wherein Q₁ to Q₉, Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁ to Q₃₉ may eachindependently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxylgroup, a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group ora saltthereof, a sulfonic acid group ora salt thereof, a phosphoric acid groupor a salt thereof, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₁-C₆₀ alkylthiogroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedheterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₇-C₆₀ alkyl aryl group, asubstituted or unsubstituted C₇-C₆₀ aryl alkyl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted C₂-C₆₀ alkyl heteroaryl group, asubstituted or unsubstituted C₂-C₆₀ heteroaryl alkyl group, asubstituted or unsubstituted C₁-C₆₀ heteroaryloxy group, a substitutedor unsubstituted C₁-C₆₀ heteroarylthio group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, or asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group.

Hereinafter, exemplary compounds and organic light-emitting devicesaccording to one or more embodiments will be described in further detailwith reference to Synthesis Examples and Examples, however, the presentdisclosure is not limited thereto. The wording “B was used instead of A”used in describing Synthesis Examples means that an identical molarequivalent of B was used in place of A.

EXAMPLES Synthesis Example 1: Synthesis of Compound 1

(1) Synthesis of Compound 1A(1)

5.2 grams (g) (33.1 millimole (mmol)) of 2-a phenylpyridine and 5.2 g(14.7 mmol) of iridium chloride were mixed with 120 milliliters (mL) of2-ethoxyethanol and 40 mL of deionized water (DI water). Then, themixture was stirred under reflux for about 24 hours to carry out areaction, and then the temperature was allowed to cool to roomtemperature. A solid formed therefrom was separated by filtration. Thesolid was washed sufficiently with DI water, methanol, and hexanes inthe stated order and dried in a vacuum oven to thereby obtain 8.2 g ofCompound 1A (yield: 92%). The resulting Compound 1A was used in thefollowing reaction without any further purification.

(2) Synthesis of Compound 1A

1.6 g (1.5 mmol) of Compound 1A was mixed with 45 mL of methylenechloride, and a solution, in which 0.8 g (3.1 mmol) of silvertrifluoromethanesulfonate (AgOTf) was dissolved in 15 mL of methanol,was added thereto. Then, the mixture was stirred for 18 hours at roomtemperature while blocking light by using an aluminum foil. Theresultant was filtered through CELITE™ to remove a solid formedtherefrom and filtered under reduced pressure to thereby obtain a solid(Compound 1A). The solid was used in the following reaction without anyfurther purification.

(3) Synthesis of Compound 1B

In a nitrogen atmosphere, 1.2 grams (g) (4.8 mmol) of2-chloro-4-isopropyl pyridine and 3.1 g (7.8 mmol) of2,4-diphenyl-6-(4,4,5,5-tetramethyl-1,3,2-dioxoboran-2-yl)benzo[d]oxazolewere dissolved in 90 mL of 1,4-dioxane. Then, 2.3 g (21.2 mmol) ofpotassium carbonate (K₂CO₃) was dissolved in 40 mL of DI water, followedby addition of the reaction mixture and 0.41 g (0.35 mmol) of apalladium catalyst (tetrakis(triphenylphosphine)palladium(0),Pd(PPh₃)₄). Then, the resulting mixture was stirred at 110° C. underreflux. The resulting solid underwent flash column chromatography(eluent: ethyl acetate (EA) and hexanes) to thereby obtain 2.1 g ofCompound 1A 6-(4-isopropyl pyridin-1-yl)-2,4-diphenylbenzo[d]oxazole(yield: 76%). The resulting compound was identified by high resolutionmass spectroscopy (HRMS) using matrix assisted laser desorptionionization (MALDI) and by high-performance liquid chromatography (HPLC)analysis.

HRMS (MALDI) calcd for C₂₇H₂₂N₂O: m/z: 390.49 Found: 391.37.

(4) Synthesis of Compound 1

20 mL of 2-ethoxyethanol was mixed with 1.2 g (1.7 mmol) of Compound 1Aand 0.7 g (1.9 mmol) of 6-(4-isopropylpyridin-2-yl)-2,4-diphenylbenzo[d] oxazole. The mixture was stirredunder reflux for 24 hours. Then, the temperature was then reduced. Thethus obtained mixture was concentrated under reduced pressure byevaporating the solvent to obtain a solid which then was subjected toflash column chromatography (eluent: MC and hexanes) to thereby obtain0.7 g of Compound 1 (yield: 43%). The resulting compound was identifiedby HRMS and HPLC analysis.

HRMS (MALDI) calcd for C₄₉H₃₇lrN₄O: m/z: 890.08 Found: 891.07.

Synthesis Example 2: Compound 2 (Representative Synthesis Example)

0.6 g of Compound 2 was synthesized in a similar manner as in Synthesisof Compound 1, except that 5-(methyl-d3)-2-phenylpyridine was usedinstead of 2-phenylpyridine (yield: 38%). The resulting compound wasidentified by HRMS and HPLC analysis.

HRMS (MALDI) calcd for C₅₁H₃₅D₆lrN₄O: m/z: 924.17 Found: 925.31.

Example 1

A glass substrate, on which ITO is patterned as an anode, was cut to asize of 50 millimeters (mm)×50 mm×0.5 mm, sonicated in isopropyl alcoholand DI water for 5 minutes each, and cleaned by exposure to ultraviolet(UV) rays and ozone for 30 minutes. Subsequently, the ITO-patternedglass substrate was mounted on a vacuum-deposition device.

Compound HT3 and Compound F12 (p-dopant) were co-vacuum-deposited on theanode at a weight ratio of 98:2 to form a hole injection layer having athickness of 100 Å. Compound HT3 was then vacuum-deposited on the holeinjection layer to form a hole transport layer having a thickness of1,650 Å to thereby form a hole transport layer.

Subsequently, Compound GH3 (as a host) and Compound 1 (as a dopant) wereco-deposited on the hole transport layer at a weight ratio of 92:8 toform an emission layer having a thickness of 400 Å.

Compound ET3 and LiQ (n-dopant) were co-deposited at a volume ratio of50:50 on the emission layer to form an electron transport layer having athickness of 350 Å, LiQ was vacuum-deposited on the electron transportlayer to form an electron injection layer having a thickness of 10 Å,and Al was vacuum-deposited on the electron injection layer to form acathode having a thickness of 1,000 Å, thereby completing themanufacture of an organic light-emitting device.

Example 2 and Comparative Examples 1 to 3

Organic light-emitting devices (OLEDs) were manufactured in a similarmanner as in Example 1, except that the compounds shown in Table 2 wereused instead of Compound 1 as a dopant in the formation of an emissionlayer.

The driving voltage (Volts, V), maximum emission wavelength (λ_(max),nm) of the emission spectrum, maximum external quantum efficiency (maxEQE, relative value), and roll-off ratio (%) of the OLEDs manufacturedin Examples 1 and 2 and Comparative Examples 1 to 3 were evaluated. Theresults thereof are shown in Table 2. A Keithley 2400 current voltmeterand a luminance meter (Minolta Cs-1000A) were used in evaluation. Theroll-off ratio was calculated according to Equation 20.

Roll-off ratio={1−(efficiency/maximum luminescence efficiency)}×100%  Equation 20

TABLE 2 Driving Molecular voltage λ_(max) Max EQE Roll-off No. structure(V) (nm) (%) (%) Example 1 Compound 1 4.5 526 22 14 Example 2 Compound 24.4 527 22 13 Comparative Compound A 4.8 529 19 17 Example 1 ComparativeCompound B 5.2 522 18 22 Example 2 Comparative Compound C 5.4 509 17 21Example 3

Referring to the results of Table 2, the organic light-emitting devicesof Examples 1 and 2 were found to have an excellent external quantumefficiency, low driving voltage, and low roll-off ratio. In addition,the organic light-emitting devices of Examples 1 and 2 were each foundto have a lower driving voltage and lower roll-off ratio and a higherexternal quantum efficiency than the organic light-emitting devices ofComparative Examples 1 to 3.

The organometallic compound may have excellent electricalcharacteristics and thermal stability. In particular, crystallization ofthe organometallic compound may be prevented due to a high glasstransition temperature, and electrical mobility may be improved.Accordingly, an electronic device, e.g., an organic light-emittingdevice, including the organometallic compound may have a low drivingvoltage, a high efficiency, a long lifespan, a reduced roll-off ratio,and a relatively narrow FWHM of an emission peak in an EL spectrum.

Accordingly, by using the organometallic compound, an organiclight-emitting device with excellent quality may be realized. Inaddition, an electronic apparatus including the organic light-emittingdevice may be provided.

It should be understood that the exemplary embodiments described hereinshould be considered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each exemplaryembodiment should typically be considered as available for other similarfeatures or aspects in other exemplary embodiments. While one or moreexemplary embodiments have been described with reference to the examplesand figure, it will be understood by those of ordinary skill in the artthat various changes in form and details may be made therein withoutdeparting from the spirit and scope as defined by the following claims.

What is claimed is:
 1. An organometallic compound represented by Formula1:M₁(Ln₁)_(n1)(Ln₂)_(n2)   Formula 1 wherein, in Formula 1, M₁ is atransition metal, Ln₁ is a ligand represented by Formula 1A, Ln₂ is aligand represented by Formula 1B, n1 is 1 or 2, and n2 is 1 or 2:

wherein, in Formulae 1A and 1B, X₁ is C or N, and X₂ is C or N, CY₁ andCY₂ are each independently a C₅-C₃₀ carbocyclic group or a C₁-C₃₀heterocyclic group, CY₃ is a 6-membered N-containing heterocyclic group,a 6-membered N-containing heterocyclic group condensed with a C₅-C₃₀carbocyclic group, or a 6-membered N-containing heterocyclic groupcondensed with a C₅-C₃₀ carbocyclic group or a C₁-C₃₀ heterocyclicgroup, CY₄₁ is a 5-membered carbocyclic group or a 5-memberedheterocyclic group, R₁₀, R₂₀ to R₃₀, and R₄₀ to R₄₂ are eachindependently hydrogen, deuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxylgroup, a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, a phosphoric acidgroup or a salt thereof, a substituted or unsubstituted C₁-C₆₀ alkylgroup, a substituted or unsubstituted C₂-C₆₀ alkenyl group, asubstituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₁-C₆₀alkylthio group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group,a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₂-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₇-C₆₀alkyl aryl group, a substituted or unsubstituted C₇-C₆₀ aryl alkylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedC₂-C₆₀ alkyl heteroaryl group, a substituted or unsubstituted C₂-C₆₀heteroaryl alkyl group, a substituted or unsubstituted C₁-C₆₀heteroaryloxy group, a substituted or unsubstituted C₁-C₆₀heteroarylthio group, a substituted or unsubstituted monovalentnon-aromatic condensed polycyclic group, a substituted or unsubstitutedmonovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —Ge(Q₁)(Q₂)(Q₃), —N(Q₄)(Q₅), —B(Q₆)(Q₇), —P(Q₈)(Q₉), or—P(═O)(Q₈)(Q₉), two or more of a plurality of R₁₀(s) are optionallybonded together to form a substituted or unsubstituted C₅-C₃₀carbocyclic group or a substituted or unsubstituted C₁-C₃₀ heterocyclicgroup, two or more of a plurality of R₂₀(s) are optionally bondedtogether to form a substituted or unsubstituted C₅-C₃₀ carbocyclic groupor a substituted or unsubstituted C₁-C₃₀ heterocyclic group, two or moreof a plurality of R₃₀(s) are optionally bonded together to form asubstituted or unsubstituted C₅-C₃₀ carbocyclic group or a substitutedor unsubstituted C₁-C₃₀ heterocyclic group, two or more of a pluralityof R₄₀(s) are optionally bonded together to form a substituted orunsubstituted C₅-C₃₀ carbocyclic group or a substituted or unsubstitutedC₁-C₃₀ heterocyclic group, two or more adjacent groups of R₁₀, R₂₀, R₃₀,and R₄₀ to R₄₂ are optionally bonded together to form a substituted orunsubstituted C₅-C₃₀ carbocyclic group or a substituted or unsubstitutedC₁-C₃₀ heterocyclic group, b10, b20, and b30 are each independently 1,2, 3, 4, 5, 6, 7, 8, 9, or 10, b40 is 1, 2, 3, 4, 5, or 6, * and *′ eachrepresented on bonding site to M₁, and at least one substituent of thesubstituted C₅-C₃₀ carbocyclic group, the substituted C₁-C₃₀heterocyclic group, the substituted C₁-C₆₀ alkyl group, the substitutedC₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group, thesubstituted C₁-C₆₀ alkoxy group, the substituted C₁-C₆₀ alkylthio group,the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₇-C₆₀ alkyl aryl group, the substituted C₇-C₆₀aryl alkyl group, the substituted C₆-C₆₀ aryloxy group, the substitutedC₆-C₆₀ arylthio group, the substituted C₁-C₆₀ heteroaryl group, thesubstituted C₂-C₆₀ alkyl heteroaryl group, the substituted C₂-C₆₀heteroaryl alkyl group, the substituted C₁-C₆₀ heteroaryloxy group, thesubstituted C₁-C₆₀ heteroarylthio group, the substituted monovalentnon-aromatic condensed polycyclic group, and the substituted monovalentnon-aromatic condensed heteropolycyclic group is: deuterium, —F, —Cl,—Br, —I, —SF₅, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group,a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, a phosphoric acidgroup or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, or a C₁-C₆₀ alkylthiogroup; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, or a C₁-C₆₀ alkylthio group, eachsubstituted with at least one of deuterium, —F, —Cl, —Br, —I, —SF₅,—CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group,a nitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₇-C₆₀ alkyl aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀arylthio group, a C₁-C₆₀ heteroaryl group, a C₂-C₆₀ alkyl heteroarylgroup, a C₁-C₆₀ heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃),—Ge(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), —P(Q₁₈)(Q₁₉),—P(═O)(Q₁₈)(Q₁₉), or a combination thereof; a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₇-C₆₀ alkyl arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a C₂-C₆₀ alkyl heteroaryl group, a C₁-C₆₀heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, a monovalentnon-aromatic condensed polycyclic group, or a monovalent non-aromaticcondensed heteropolycyclic group; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₇-C₆₀ alkyl arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a C₂-C₆₀ alkyl heteroaryl group, a C₁-C₆₀heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, a monovalentnon-aromatic condensed polycyclic group, or a monovalent non-aromaticcondensed heteropolycyclic group, each substituted with at least one ofdeuterium, —F, —Cl, —Br, —I, —SF₅, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid group or a salt thereof, a sulfonic acid group or a salt thereof, aphosphoric acid group or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₁-C₆₀alkylthio group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₇-C₆₀ alkyl aryl group, a C₇-C₆₀ aryl alkyl group,a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroarylgroup, a C₂-C₆₀ alkyl heteroaryl group, a C₂-C₆₀ heteroaryl alkyl group,a C₁-C₆₀ heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—Ge(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₄)(Q₂₅), —(Q₂₆)(Q₂₇), —P(═O)(Q₂₈)(Q₂₉), or acombination thereof; or —Si(Q₃₁)(Q₃₂)(Q₃₃), —Ge(Q₃₁)(Q₃₂)(Q₃₃),—N(Q₃₄)(Q₃₅), —B(Q₃₆)(Q₃₇), or —P(═O)(Q₃₉)(Q₃₉), wherein Q₁ to Q_(9,)Q₁₁ to Q_(19,) Q₂₁ to Q_(29,) and Q₃₁ to Q₃₉ are each independentlyhydrogen, deuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₁-C₆₀ alkylthiogroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedheterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₇-C₆₀ alkyl aryl group, asubstituted or unsubstituted C₇-C₆₀ aryl alkyl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted C₂-C₆₀ alkyl heteroaryl group, asubstituted or unsubstituted C₂-C₆₀ heteroaryl alkyl group, asubstituted or unsubstituted C₁-C₆₀ heteroaryloxy group, a substitutedor unsubstituted C₁-C₆₀ heteroarylthio group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, or asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group.
 2. The organometallic compound of claim 1,wherein M₁ is iridium (Ir), platinum (Pt), osmium (Os), titanium (Ti),zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), thulium (Tm),or rhodium (Rh).
 3. The organometallic compound of claim 1, wherein M₁is Ir, and a sum of n1 and n2 is
 3. 4. The organometallic compound ofclaim 1, wherein CY₁ and CY₂ are each independently a benzene group, anaphthalene group, a 1,2,3,4-tetrahydronaphthalene group, a phenanthrenegroup, a pyridine group, a pyrimidine group, a pyrazine group, apyridazine group, a triazine group, a quinoline group, an isoquinolinegroup, a quinoxaline group, a quinazoline group, a phenanthroline group,a benzofuran group, a benzothiophene group, a fluorene group, acarbazole group, a dibenzofuran group, a dibenzothiophene group, adibenzosilole group, an azafluorene group, an azacarbazole group, anazadibenzofuran group, an azadibenzothiophene group, or anazadibenzosilole group.
 5. The organometallic compound of claim 1,wherein CY₃ is a pyridine group, a pyrimidine group, a pyrazine group, apyridazine group, a triazine group, a quinoline group, an isoquinolinegroup, a benzoquinoline group, a benzoisoquinoline group, aphenanthroline group, a quinoxaline group, or a quinazoline group. 6.The organometallic compound of claim 1, wherein CY₄₁ is acyclopentadiene group, a furan group, a thiophene group, a selenophenegroup, a pyrrole group, a borole group, an oxazole group, a thiazolegroup, a selenazole group, an imidazole group, an azaborole group, anoxaborole group, a thiaborole group, a selenaborole group, or a diborolegroup.
 7. The organometallic compound of claim 1, wherein CY₁ isrepresented by one of Formulae 1-1 to 1-16:

wherein, in Formulae 1-1 to 1-16, R₁₁ to R₁₄ are each independentlyunderstood by referring to the description of R₁₀ in claim 1, providedthat R₁₁ to R₁₄ are each not hydrogen, * indicates a binding site to M₁,and *′ indicates a binding site to an adjacent atom.
 8. Theorganometallic compound of claim 1, wherein CY₂ is represented by one ofFormula 2-1 to 2-16:

wherein, in Formulae 2-1 to 2-16, R₂₁ to R₂₄ are each independentlyunderstood by referring to the description of R₂₀ in claim 1, providedthat R₂₁ to R₂₄ are each not hydrogen, * indicates a binding site to M₁,and *″ indicates a binding site to an adjacent atom.
 9. Theorganometallic compound of claim 1, wherein CY₃ is represented by one ofFormulae 3-1 to 3-16:

wherein, in Formulae 3-1 to 3-16, R₃₁ to R₃₄ are each independentlyunderstood by referring to the description of R₃₀ in claim 1, providedthat R₃₁ to R₃₄ are each not hydrogen, and * indicates a binding site toM₁, and *′ indicates a binding site to an adjacent atom.
 10. Theorganometallic compound of claim 1, wherein R₁₀, R₂₀, R₃₀, and R₄₀ toR₄₂ are each independently: hydrogen, deuterium, —F, —Cl, —Br, —I,—SF_(5,) —CD_(3,) —CD₂H, —CDH_(2,) —CF_(3,) —CF₂H, —CFH_(2,) a hydroxylgroup, a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, a phosphoric acidgroup or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, ora C₁-C₂₀ alkylthio group; a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group,or a C₁-C₂₀ alkylthio group, each substituted with at least one ofdeuterium, —F, —Cl, —Br, —I, —SF₅, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid group or a salt thereof, a sulfonic acid group or a salt thereof, aphosphoric acid group or a salt thereof, a C₁-C₁₀ alkyl group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, an adamantanyl group, a norbornanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, abenzene group, a naphthyl group, a pyridinyl group, a pyrimidinyl group,or a combination thereof; a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a benzene group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, or animidazopyrimidinyl group; a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a benzene group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, or animidazopyrimidinyl group, each substituted with at least one ofdeuterium, —F, —Cl, —Br, —I, —SF₅, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid group or a salt thereof, a sulfonic acid group or a salt thereof, aphosphoric acid group or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a C₁-C₂₀ alkylthio group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, abenzene group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, an imidazopyrimidinyl group, or a combination thereof; or—Si(Q₁)(Q₂)(Q₃), —Ge(Q₁)(Q₂)(Q₃), —N(Q₄)(Q₅), —B(Q₆)(Q₇), or—P(═O)(Q₈)(Q₉), wherein Q₁ to Q₉ are each independently: —CH₃, —CD₃,—CD₂H, —CDH₂, —CH₂CH₃, —CH₂CD₃, —CH₂CD₂H, —CH₂CDH₂, —CHDCH₃, —CHDCD₂H,—CHDCDH₂, —CHDCD₃, —CD₂CD₃, —CD₂CD₂H, or —CD₂CDF₁₂, an n-propyl group,an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butylgroup, a tert-butyl group, an n-pentyl group, an iso-pentyl group, asec-pentyl group, a tert-pentyl group, a benzene group, or a naphthylgroup; or an n-propyl group, an iso-propyl group, an n-butyl group, aniso-butyl group, a sec-butyl group, a tent-butyl group, an n-pentylgroup, an iso-pentyl group, a sec-pentyl group, a tent-pentyl group, abenzene group, or a naphthyl group, each substituted with at least oneof deuterium, a C₁-C₁₀ alkyl group, a benzene group, or a combinationthereof.
 11. The organometallic compound of claim 1, wherein R₁₀, R₂₀,R₃₀, and R₄₀ to R₄₂ are each independently: hydrogen, deuterium, —F,—Cl, —Br, —I, —SFS, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, or a C₁-C₆₀ alkylthio group; a group represented by one ofFormulae 9-1 to 9-61, 9-201 to 9-237, 10-1 to 10-129, or 10-201 to10-350; or —Si(Q₁)(Q₂)(Q₃), —Ge(Q₁)(Q₂)(Q₃), or —N(Q₄)(Q₅):

wherein, in Formulae 9-1 to 9-61, 9-201 to 9-237, 10-1 to 10-129, and10-201 to 10-350, * indicates a binding site to an adjacent atom, “Ph”represents a benzene group, “TMS” represents a trimethylsilyl group, and“TMG” represents a trimethylgermyl group.
 12. The organometalliccompound of claim 1, wherein Ln₂ is represented by Formula 21-1 orFormula 21-2:

wherein, in Formulae 21-1 and 21-2, CY_(3,) R₃₀, R_(41,) R_(42,) and b30are as defined in claim 1, X₄₁ is N, B, or C(R₄₄), X₄₂ is O, S, Se,N(R₄₅), B(R₄₆), or C(R₄₅)(R₄₆), R₄₃ to R₄₆ are each independently asdefined for R₄₀ in claim 1, and * and *′ each indicate a binding site toM₁.
 13. The organometallic compound of claim 1, wherein theorganometallic compound is a compound represented by Formula 31-1 orFormula 31-2:

wherein, in Formulae 31-1 and 31-2, M₁, n1, n2, R₄₁, and R₄₂ are asdefined in claim 1, X₁₁ is C(R₁₁) or N, X₁₂ is C(R₁₂) or N, X₁₃ isC(R₁₃) or N, and X₁₄ is C(R₁₄) or N, X₂₁ is C(R₂₁) or N, X₂₂ is C(R₂₂)or N, X₂₃ is C(R₂₃) or N, and X₂₄ is C(R₂₄) or N, X₃₁ iS C(R₃₁) or N,X₃₂ is C(R₃₂) or N, X₃₃ is C(R₃₃) or N, and X₃₄ is C(R₃₄) or N, X₄₁ isN, B, or C(R₄₄), X₄₂ is O, S, Se, N(R₄₅), B(R₄₆), or C(R₄₅)(R₄₆), R₁₁ toR₁₄ are each independently as defined for R₁₀ in claim 1, R₂₁ to R₂₄ areeach independently as defined for R₂₀ in claim 1, R₃₁ to R₃₄ are eachindependently as defined for R₃₀ in claim 1, R₄₃ to R₄₆ are eachindependently as defined for R₄₀ in claim 1, at least two of R₁₁ to R₁₄are optionally bonded together to form a C₅-C₃₀ carbocyclic groupunsubstituted or substituted with at least one R_(10a) or a C₁-C₃₀heterocyclic group unsubstituted or substituted with at least oneR_(10a), at least two of R₂₁ to R₂₄ are optionally bonded together toform a C₅-C₃₀ carbocyclic group unsubstituted or substituted with atleast one R_(10a) or a C₁-C₃₀ heterocyclic group unsubstituted orsubstituted with at least one R_(10a), at least two of R₃₁ to R₃₄ areoptionally bonded together to form a C₅-C₃₀ carbocyclic groupunsubstituted or substituted with at least one R_(10a) or a C₁-C₃₀heterocyclic group unsubstituted or substituted with at least oneR_(10a), and R_(10a) is as defined for R₁₀ in claim
 1. 14. Theorganometallic compound of claim 1, wherein the organometallic compoundis one of Compounds 1 to 132:


15. An organic light-emitting device, comprising: a first electrode; asecond electrode; and an organic layer located between the firstelectrode and the second electrode, wherein the organic layer comprisesan emission layer, and wherein the organic layer further comprises atleast one of the organometallic compound of claim
 1. 16. The organiclight-emitting device of claim 15, wherein the emission layer comprisesthe organometallic compound.
 17. The organic light-emitting device ofclaim 16, wherein the emission layer further comprises a host, and anamount of the host in the emission layer is greater than an amount ofthe organometallic compound in the emission layer.
 18. The organiclight-emitting device of claim 16, wherein the emission layer emitsgreen light having a maximum emission wavelength in a range of about 500nanometers to about 600 nanometers.
 19. The organic light-emittingdevice of claim 16, wherein the first electrode is an anode, the secondelectrode is a cathode, the organic layer further comprises a holetransport region located between the first electrode and the emissionlayer, and an electron transport region located between the emissionlayer and the second electrode, the hole transport region comprises ahole injection layer, a hole transport layer, an electron blockinglayer, a buffer layer, or a combination thereof, and the electrontransport region comprises a hole blocking layer, an electron transportlayer, an electron injection layer, or a combination thereof.
 20. Anelectronic apparatus, comprising the organic light-emitting device ofclaim 15.